Pump systems for liquids

ABSTRACT

A system for pumping of liquid under pressure, in which a pressure switch is adapted to control the starting and stopping of the pump within a safe pressure range, and in the event of malfunction of the pressure switch, the serviceline and associated plumbing is isolated from the pump to protect against development of pressures in the serviceline which might damage the plumbing.

United States Patent 9 Gr tz 1 June 4, 1974 PUMP SYSTEMS FOR LIQUIDS3,141,475 7/1964 Guinard ct 111 137/568 I 3,150,684 9/1964 Guinard et ul137/568 [75] lnvemor- Rock Ark-1 3.322.145 5/1967 P105581 137/517 [73]Assignee: Jacuzzi Bros. Incorporated, Littl 3,739,810 6/1973 Horan; Jr.1 4l7/38 X Rock, Ark. Primary Examiner Clarence R. Gordon [22] Ffled'1973 Assistant EtanzinerRichard Sher [2i] Appl. No.: 327,955

1 1 ABSTRACT [52] US. Cl 417/26, l37/505.44, 137/6253,

251/] [8, 251/21O 417/38 A system for pumpmg of l1qu1d under pressure.1n 1511 1m. (:1. F04b 49/08 which a Pressure Switch is adapted tocontrol the 15s1 Field of Search 417/38, 43, 31, 441, 507. mg andStopping of the P Within a Safe Pressurc 7/26, 28 137/568, 625311150544. range, and in the event of malfunction of the pressure 251/210118, switch, the serviceline and associated plumbing is isolated fromthe pump to protect against development [56] References Cited ofpressures in the serviceline which might damage the UNITED STATESPATENTS plumbmg' 2,737,975 3/1956 Wilkins 137/505.44 4 Claims, 7 DrawingFigures PATENTEDJUN 4 m4 SHEET 2 I]? 3 PATENTEU 4 I974 SHEET 3 0F 3 FEG.

1 PUMP SYSTEMS FOR LIQUIDS My invention relates to systems for pumpingof liquid under pressure and more particularly to water pressuresystems.

While the system of the present invention can be employed in general tothe pumping of liquids under pressure, it is more specifically adaptedto water pressure systems and will be described with respect to itsapplication to such a system.

In water pressure systems of the type to which the present inventionrelates, a pump supplies one or more branch service lines, eachterminating in a service valve. A pressure switch normally exposed topressures within a service line, is adjusted to energize the pump drivemotor when the pressure in the serviceline drops to a predetermined lowvalue, say of the order of or pounds per square inch, and de-energizethe pump drive motor should the pressure in the serviceline reach apredetermined high value of the order of say 50 pounds per square inch.

Where the system involves a number of branch service lines or, in somecases, where the pump is not matched to the system which it is tosupply, the pump may be capable of developing pressures far in excess ofthe shut-down value setting of the pressure switch, and such pressures,if permitted to develop in the service line, can wreck havoc with theplumbing associated with this portion of the system. This kind of adisruptive situation can develop should the pressure switch, forexample, fail to function to de-energize the pump motor when the servicedemand ceases, thus allowing the pump to continue functioning despitethe fact that there is no demand for service. Under the circumstances,there will be a build up of pressure in the serviceline, to thecapability of the pump, and this could be destructive of plumbingassociated with the service line.

Among the objects of my invention are:

1. To provide a novel and improved pump system for supplying liquidunder pressure within a safe range and which will preclude a rise inpressure in the serviceline to values dangerous to existing plumbingshould the pump fail to shut down when the demand for service ceases.

2. To provide a novel and improvedpump system having automatic pumpstart and stop control, wherein upon failure of the stop control to shutdown a pump, the serviceline of the system is isolated from the pump.

Additional objects of my invention will be brought out in the followingdescription of a preferred embodiment of the same, taken in conjunctionwith the accompanying drawings wherein;

FIG. I is a view depicting one type of water system and the applicationof the present invention hereto;

FIG. 2 is a view in perspective of a control assembly in such system andwhich embodies the present invention;

FIG. 3 is a view in section taken through pressure regulator valveassembly constituting an important component of the control assembly ofFIG. 2;

FIGS. 4a, 4b, and 4c are related views depicting the manner of operationof a valve involved in the pressure mersible type illustrated in thesystem of FIG. I, and a curve depicting the corresponding pressureswhich I would exist in the serviceline of the system with the presentinvention incorporated therein.

Referring to the drawings for details of my invention in its preferredform, I have illustrated the invention in FIG. 1 as embodied in a systemof the submersible pump type which involves a submersible pump 1 anddrive motor 2, both submerged below water level in a well casing 3 fromwhich the pump discharges through a line 5 to a control assembly 7 suchas depicted in the enlarged view in FIG. 2, and from which a mainserviceline 9 extends. The serviceline may couple to a plurality ofbranch servicelines, each terminating in a service valve (notillustrated but which may be of any conventional type).

The control assembly 7 includes a novel and improved pressure regulatingvalve assembly 11 constituting the heart of the present invention.

This pressure regulating valve assembly involves a housing 12 having athreaded inlet opening 13 at one end for connection of the pumpdischarge line 5, to receive liquid at the prevailing pump pressure, anda threaded outlet opening 15 at the opposite end for connection of theservice line 9.

The inlet opening is blocked off by the partition 17 having a threadedopening 19 therethrough substantially at right angles to the axis of theinlet opening, and into which a threaded fitting 21 is installed toprovide a valve seat 23.

In axial alignment with such valve seat, is a valve 25 supported by abracket 27 from a diaphram 29 spanning an opening in the housing andretained in such position by a spring housing 31 threadedly installed insuch opening.

In the spring housing is a compression spring 33 seating at one endagainst the diaphragm and at its other end, engaging the end of anadjusting screw 35 installed through the end of the spring housing,leaving the screw head 37 exposed for adjustment purposes. Theadjustment of the spring determines the value of the regulated pressureat the outlet opening 15 of the valve assembly in accordance withconventional practice.

A screen 41 in the flow path between the inlet opening 13 and thepartition opening 19, will serve to screen out any debris in the watercoming from the pump.

As thus far described, the pressure regulating valve assembly receivesliquid under pressure through the inlet opening from the pump, whenrunning, such liquid passing through the valve and, depending onconditions beyond the outlet opening, will build up a back pressureagainst the diaphragm in opposition to the compression spring, and whensuch back pressure overcomes the pressure setting of the spring, thediaphragm will begin to move toward and compress the spring, in thecourse of which, it will carry the valve in the direction of seating.During such movement of the valve, a resulting increase in pressure dropacross the valve will result in a tendency for the diaphragm to berestored to its original position. As a result, the valve will hoverabout a position which will enable the pressure at the outlet opening tobe maintained at substantially a value corresponding to the setting ofthe spring, despite the pump pressure at the inlet end of the valveassembly.

Threadedly coupled to the housing of the pressure regulator valveassembly and exposed to the pressure on the outlet side of the valve, isa pressure switch 43, which, by reason of such coupling, is exposed tothe pressure prevailing in the serviceline of this system. This pressureswitch is connected in the conventional manner, in circuit with themotor 2 which drives the pump 1 and is adjusted to connect the pumpmotor in circuit when the pressure in the serviceline drops to apredetermined low value, say of the order of or 30 pounds per squareinch, and disconnect such pump motor when the pressure in theserviceline raises to a higher predetermined value, which is still safefor the plumbing associated with the serviceline.

In conjunction with the pressure regulator valve assembly and thepressure switch, is a small expandable cell assembly 45 or pressuredevice whose function is to maintain pressure in the serviceline duringquiescent conditions of the system, and upon opening of a serviceline,to quickly drop the pressure to the low pressure setting of the pressureswitch to start the pump motor, while at other times delaying the startup of the pump motor in the event of small leaks inthe system. Suchassembly comprises a rubber bladder 46 in a receptacle 47 which limitspermissible expansion of the bladder to a, limited volume or capacity ofthe order of 12 ounces of water.

This pressure device is preferable threadedly installed in a passageway48 in the pressure regulator housing on the low pressure side, thepassageway preferably being in alignment with the valve 25.

With such pressure maintaining device coupled into the system, thenduring closing off of demand for service, the pressure device will becharged to the pressure prevailing in the serviceline at the time ofshut off. Upon subsequently opening of a service valve the pressuredevice will promptly discharge to the pressure value at which thepressure switch will start the pump motor and cause the pump tofunction.

Though the pump may conceivably, at times, build up to pressures whichif permitted to develop in the serviceline, would likely damage plumbingassociated with the serviceline portion of the system, the pressureactually developed in the serviceline, while supplying servicerequirements, will, due to the functioning of the pressure regulator beconsiderably less andat a safe value, as determined by the setting ofthe pressure regulator spring. I

It is, however, during that period in the operation of the system, whenthe demands from service are approaching cut-off, that pressure troublein the serviceline can be expected, for, if, during this period ofoperation, high pressures are permitted'to develop in the serviceline,such pressures will be maintained by the pressure device, and willcontinue to be maintained until the next service demand on the system.Thus the plumbing associated with the serviceline, under theseconditions, might well be exposed to destructive pressures for extendedperiods of time and with probable resulting damage to such plumbing. Itbecomes imperative therefore, to prevent the development of suchdestructive pressures during the closing of a service valve interminating demands for service.

This requirement will normally be met by satisfactory functioning of thepressure switch, which is set to shut down the pump while service linepressure is still at a safe value. However, should the pressure switchmalfunction, the pump will continue running despite the closing of allservice valves and under this condition,

the pump, in a conventional system, would be free to develop its maximumcapable pressure in the serviceline. The system of the presentinvention, in its preferred form, solves this latter problem through asimple modification of the structure of the pressure regulator valveassembly. v

in accordance with such modification, the valve seat 23 is renderedimperfect by the provision of one or more small V notches 24 in the seatitself, and the valve component 25 is provided with a sealing disc 55 ofrubber or equivalent material, preferably of neo- Pr n rubber 59:6 qqrqmsrt held. t a backing plug 57 of metal which is threaded intothesupporting bracket 27. The metal backing plug. referably extends intothe passageway 48 and is provided at its remote end with a screw driverslot. Thus, upon removal of the pressure device, the valve may beinstalled or removed by way of the passageway with the use of commontools.

The notches may be of 60 angle, to. a depth of 0.032 inches across thevalve seat, depending on characteristics of the sealing material.

Actual sealing material and notch dimensions may vary to satisfy varyingconditions in different systems.

In maintaining a regulated pressure at the outlet side of the pressureregulator valve, the spacing of the valve from its valve seat will varywith service demands. As the demands become less, as during closing of aservice valve, the valve will move toward its closingposition.Ultimately, as the serviceline demand approaches zero, the valve willseat except for the notches which provide by-pass leak passages for alimited amount of flow. When such limited amount of flow exceeds thedwindling demand of service, a pressure build-up will be initiated inthe serviceline, which, within a rise of the order of 9 pounds, forexample, depending on the character of the sealing disc material andsize of notches, will compress the sealing disc into the notches andcompletely block off the serviceline from the pump,

whereby, if in the mean time the pressure switch had malfunctioned andfailed to shut down the pump motor, the continued operation of the pumpcould not effect prevailing pressure in the serviceline, astheserviceline would now be completely isolated or blocked off from thepump.

, Thus, though the pump itself might be capable of developingexcessively high pressures, which would be destructive to plumbingassociated with the serviceline, the serviceline portion of the systemwould now be protected against the development of such excessively highpressures. r

Through the use of notches to provide the by-pass paths around thevalve, as distinguished from small holes or the like, clogging isavoided, as the notches become self cleaning during openings of thevalve.

As an example of an installation embodying the present invention,reference will be made to the characteristic curves of FIG. 5 whichrelate to a typical submserible pump system such as illustrated in FIG.1.

In this particular system, the pump performance curve 61 indicates thatat a discharge of A gallons per minute, the pump was capable ofdeveloping a maximum pressure exceeding pounds per square inch, far inexcess of what may be deemed a safe value for plumbing. The pressureregulating valve was capable of blocking .off the service line from thepump at a safe serviceline should the pressure switch malfunction andthe pump continue to run.

Relative to such safe value pressure as indicated by the referencenumeral 63, the pressure regulator valve assembly is adjusted to deliverat pressure below such value along a curve 67, starting at the cut-inpressure 69 of the pressure switch, with the cut-off pressure setting ofthe pressure switch at the value designated by the reference numeral 65,all as clearly depicted in FIG. 5.

From the foregoing description of my invention in its preferred form asapplied to a water system, it will be apparent that the same isapplicable for the pumping of liquids in general and is subject toalteration and modification without departing from the underlyingprinciples involved. I, accordingly, do not desire to be limited in myprotection to the specific details illustrated and described, except asmay be necessitated by the appended claims.

1 claim:

1. A system for pumping liquid comprising a pump, drive means coupled tosaid pump for driving the same, a serviceline terminating in a servicevalve, said pump being capable of developing pressures above apredetermined value of pressure in said service line deemed a safe valuefor operation of said system, means in said system between said pump andsaid serviceline for reducing pump pressure to operating pressure alonga curve below said predetermined value, said means for reducing suchpump pressure to such operating pressure below said predetermined value,including a pressure regulator valve assembly comprising a housinghaving an input opening for receiving discharge from said pump and anoutlet opening for discharging liquid at such reduced operating pressureto said serviceline, a valve and associated valve seat in the flow pathbetween said openings, means responsive to a pressure below suchoperating pressure curve for energizing said drive means to start saidpump, said means also being responsive to a cut-off pressure betweensaid predetermined value and such lower operating pressure curve forde-energizing said drive means to stop said pump, and means, uponfailure of said pressure responsive means to deenergize said drive meansand stop said pump, adapted to isolate said serviceline from said pumpat a safe pressure in said serviceline, said service line isolatingmeans including a bypass passageway in by-pass relationship to saidvalve, and means for closing said by-pass passageway to continued flowfrom said pump, following the seating of said valve and when theserviceline pressure is of the order of said predetermined value.

2. A system in accordance with claim 1, characterized by said by-passpassageway including at least one notch in said valve seat, said valveincluding a sealing disc adapted to deform under pressure and seal saidnotch following initial seating of said valve.

3. A system in accordance with claim 2, characterized by said safeserviceline isolation pressure being of the order of 9 pounds per squareinch above the cut-off pressure of said pressure responsivede-energizing means.

4. A system in accordance with claim 1, characterized by said pumpstarting and stopping means being in constant pressure communicationwith said serviceline.

1. A system for pumping liquid comprising a pump, drive means coupled tosaid pump for driving the same, a serviceline terminating in a servicevalve, said pump being capable of developing pressures above apredetermined value of pressure in said service line deemed a safe valuefor operation of said system, means in said system between said pump andsaid serviceline for reducing pump pressure to operating pressure alonga curve below said predetermined value, said means for reducing suchpump pressure to such operating pressure below said predetermined value,including a pressure regulator valve assembly comprising a housinghaving an input opening for receiving discharge from said pump and anoutlet opening for discharging liquid at such reduced operating pressureto said serviceline, a valve and associated valve seat in the flow pathbetween said openings, means responsive to a pressure below suchoperating pressure curve for energizing said drive means to start saidpump, said means also being responsive to a cut-off pressure betweensaid predetermined value and such lower operating pressure curve forde-energizing said drive means to stop said pump, and means, uponfailure of said pressure responsive means to deenergize said drive meansand stop said pump, adapted to isolate said serviceline from said pumpat a safe pressure in said serviceline, said serviceline isolating meansincluding a by-pass passageway in by-pass relationship to said valve,and means for closing said by-pass passageway to continued flow fromsaid pump, following the seating of said valve and when the servicelinepressure is of the order of said predetermined value.
 2. A system inaccordance with claim 1, characterized by said by-pass passagewayincluding at least one notch in said valve seat, said valve including asealing disc adapted to deform under pressure and seal said notchfollowing initial seating of said valve.
 3. A system in accordance withclaim 2, characterized by said safe serviceline isolation pressure beingof the order of 9 pounds per square inch above the cut-off pressure ofsaid pressure responsive de-energizing means.
 4. A system in accordancewith claim 1, characterized by said pump starting and stopping meansbeing in constant pressure communication with said serviceline.